Acoustic guitar is the central instrument in folk, singer-songwriter, country, bluegrass, and unplugged pop. It is also one of the most over-processed instruments in amateur mixes, where heavy-handed EQ and compression rob it of the natural dynamics that make acoustic music feel intimate. The goal of mixing acoustic guitar is to enhance what the recording captured, not to reshape it.
The frequency anatomy of a steel-string acoustic: the body resonance lives at 80 to 120 Hz (a boomy thump if it gets out of hand), the boxy mud lives at 200 to 300 Hz (the single biggest problem in 90% of acoustic recordings), the body and warmth live at 400 to 800 Hz, the pick attack and definition live at 2 to 4 kHz, and the air and sparkle live at 8 to 15 kHz. Each zone needs to be handled.
Start with a high-pass filter at 100 to 120 Hz for accompaniment guitar (when there is also bass and other instruments). Higher — up to 180 Hz — for very dense arrangements where the acoustic is pure rhythm and the bass is doing all the low end work. Solo or duo recordings can high-pass lower, around 60 to 80 Hz, because the acoustic is one of the few low-end sources.
The 200 to 300 Hz mud cut is the single most important EQ move on acoustic guitar. Sweep with a narrow boosted band of 4 to 6 dB through the 200 to 400 Hz range until you find the most boxy, hollow, cardboard-sounding frequency. That is your problem frequency. Cut it by 3 to 5 dB with a moderate Q. The acoustic will sound thinner in solo, but it will sit better in the mix and the body of the guitar will become audible without the mud.
Add air with a high shelf at 10 to 15 kHz, boosted 2 to 4 dB. This gives the guitar the polished sparkle that makes professional recordings sound expensive. Add presence with a narrow boost at 3 to 4 kHz of 1 to 3 dB if the pick attack is buried in the mix. Be careful with both — every dB of high-frequency boost adds finger noise and string squeaks.
Compression on acoustic guitar should be light. 2:1 to 3:1 ratio, slow attack (20 to 40 ms) so the pick transient survives intact, slow release. 2 to 4 dB of gain reduction on average, never more than 6 dB. The goal is to even out the dynamics enough that quiet picking and loud strumming sit in the same mix space, not to crush the instrument flat. Heavy acoustic compression sounds like an amateur move.
Stereo width on acoustic. If you have one acoustic track, double-track it: record the same part twice, hard-pan one take left and the other right. The natural micro-timing differences create real stereo width that no plugin can fake. If you cannot re-record, use a stereo doubler plugin (like Waves Doubler or stock pitch-shift trickery) — pan the original 30% left, the doubler 30% right, with the doubler delayed by 8 to 15 ms. Result: width without phase issues.
Multi-mic acoustic recordings (one mic at the 12th fret, one at the bridge, one room mic) get summed together with phase alignment. Slip the mics so the transients line up sample-accurate, then blend by ear. The 12th-fret mic gives body, the bridge mic gives attack, the room mic gives air. Each mic gets its own EQ — the 12th-fret mic gets the boxy mud cut, the bridge mic gets a high-pass at 200 Hz to keep its boomy proximity effect from doubling the 12th-fret mic's low end.
Reverb on acoustic. Use a small room or plate reverb (0.8 to 1.5 seconds decay) sent at -15 to -20 dB. EQ the reverb return to remove the low end (high-pass at 400 Hz) so it does not muddy up the mix. Acoustic guitar in solo songs can take a longer plate or hall (2 to 3 seconds) for intimacy.
Common mistakes: no mud cut (the guitar is muddy), too much high-end boost (finger noise dominates), heavy compression (kills the dynamics that make acoustic feel alive), single-tracked acoustic panned to one side (lopsided stereo), reverb on the low end (extends the mud), recording too close to the soundhole (proximity-effect boom).
Reference tracks: Taylor Swift's "folklore" for modern intimate folk, Chris Stapleton's "Tennessee Whiskey" for country, Sturgill Simpson's "Turtles All the Way Down" for outlaw country, John Mayer's "Stop This Train" for produced singer-songwriter. Each is a different aesthetic but all share the principle of clean low end and natural dynamics.